The Difference Between CMYK and Ds

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1 In this guide This guide details differences between RGB and CMYK colour gamuts, explaining why CMYK shouldbe used for commercially ped documents and finally showing how to check colour settings in various popular software packages. Please note when ordering that we do not check documents colour set up and automatically convert all colours to CMYK, in certain cases this can cause noticeable colour variation. 1. Colour Gamut Differences - CMYK v RGB 2. Converting RGB files and re-balancing colour 3. Creating Files In CMYK a. Adobe Photoshop b. Adobe InD c. Adobe Illustrator d. Microsoft Publisher 4. DOs and DON Ts - Checking Your Files before sending CMYK colours are subtractive meaning starting canvasis white and colours are added to block outparts of spectrum RGB colours are additive meaning that starting pointis a black canvas (i.e. a computer screen) and colours are added to create final image.

2 Why P files need to be CMYK The RGB colour spectrum is much larger than CMYK spectrum. i.e. re are colours that can be created in RGB that are not available CMYK. This problem is most apparent with very bright colours such as a fluorescent orange or green. Commercial presses p onto white paper using CMYK colours, in order to get best results files should be prepared with this in mind. Below shows examples of files submitted in RGB colour that have been automatically converted into CMYK before ping. Converting files to CMYK before submitting m to p will avoid any surprises with colour when final product is produced.

3 2. Converting RGB files to CMYK and re-balancing colour Using software such as photoshop is possible to readjust colour balance after conversion to more closely match intended colour output. If using RGB elements i.e. images in d stage it is worth converting elements into CMYK and rebalancing colours during d process. RGB -Original image to be used. (Notice vibrancy of blues) 3. Creating Files In CMYK CMYK - Colours are converted straight to CMYK CMYK - Colour levels are a djusted to match in photoshop. When ding any file it is important to set up and d document in CMYK colour. This will save any problems in trying to adjust colours afterwards which can be very difficult if not impossible. Not all software is able to create files in CMYK colour mode. For example Microsoft Word and Powerpoint are only able to create documents in RGB which must be converted before prinitng. If you send us a native Word or Powerpoint files we will convert m into a CMYK pdf and will send a proof for checking. Software shown in guide a. Adobe Photoshop b. Adobe InD c. Adobe Illustrator d. Microsoft Publisher Or software The software shown above represents most commonly used desktop publishing software for creatingp files however documents can be created in many or packages. If using or software key settings are as follows; Colour mode CMYK (Sometimes called process colours). Colour profile: Fogra 39 (ISO :2004). Where possible export as a PDF/x-1a:2001

4 a. Adobe Photoshop Colour settings in photoshop are determined when document is created, screen below shows correct colour settings. You can also check colour settings when a document is open by clicking on image, n mode as shown by screen on right. When creating a document set to CMYK Checking when document is open b. Adobe InD With ind colours are converted when file is exported to pdf. Selecting pdf/x-1a:2001 preset will ensure that document is CMYK. When exporting select pdf/x-1a2001 preset

5 c. Adobe Illustrator In adobe illustrator colour mode is set when document is created. When saving as a pdf select pdf/x-1a:2001 from drop down presets list. When creating document select CMYK in colour mode. When saving document as a pdf select pdf/x-1a2001 preset d. Microsoft Publisher When document is open click file - info - commercial p settings - choose colour model. This will allow you to set colour mode that you would like document to be set up in. From file menu select choose colour model Select Process colours (CMYK)

6 4. DOs and DON Ts - Checking Your Files before sending Finally, a couple of quick pointers to help you understanding issue and assist in checking. DO check proofs on screen using a colour calibrated monitor (if possible). Be aware that with uncalibrated screens colours will vary from monitor to monitor. DO p samples using a commercial proof per ensuring target profile is set to Fogra 39 DO use acrobat pro output preview tool to check how file will look when output to Fogra 39. DO use ped CMYK colour swatches to check colours if unsure. DO ask for a ped sample if you are unsure of your document s colour setup. Samples cost 10 and can be ordered by calling office. Turnaround is one working day for production + one working day for delivery. DON T check colours against desktop per samples as ir profiles will generally try to emulate RGB colours as opposed to ping true CMYK colours.